The present invention concerns a device for extracting and cooling ash from a fluidized bed.
The purpose of such a device is to extract the dry ash from the bed at 870.degree. C. and cool it to below 300.degree. C. Conveyors comprising semi-cooled screws accommodated in semi-cooled housings are known for this purpose. When the cooling system leaks, water penetrates into the interior and soaks the ash. The wet ash cakes up on the wall of the housing and clogs the conveyor, which breaks down.
Also known for extracting and cooling fluidized-bed ash are "trickle" coolers, wherein the cooling water flows through coils. The coils are in contact with the ash, which subjects them to considerable abrasion.